Drug testing for substances of abuse has been claimed as a method to detect and deter drug use by adolescents. The U.S. Supreme Court established the legality of high school drug testing programs among those engaged in extracurricular activities, and the federal government has established funding for high schools to drug test students through grants from the U.S. Department of Education. In addition, parents or guardians can purchase drug testing kits on the Internet for use at home. However, school random drug testing is a controversial issue and the efficacy, cost effectiveness, and risks of this procedure have not been established. While some supporters report favorable results from their personal experiences with school-based drug testing, formal studies published to date have not as yet shown drug testing to be an effective deterrent, and research has identified risks associated with implementation.